GHC tells me to use RankNTypes when it's already enabled

I was stumped for a while today because GHC kept telling me to turn on RankNTypes even when it was already enabled! I eventually realized this was the problem:

{-# LANGUAGE RankNTypes #-}
module Bug where

foo :: foral a. a -> a
foo x = x

$ ghc Bug.hs
[1 of 1] Compiling Bug              ( Bug.hs, Bug.o )

Bug.hs:4:15: error:
    Illegal symbol '.' in type
    Perhaps you intended to use RankNTypes or a similar language
    extension to enable explicit-forall syntax: forall <tvs>. <type>

That is, the real culprit was misspelling forall as foral.

Trac metadata

Trac field	Value
Version	8.0.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler (Type checker)
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